These people are being followed, but they're not. That's the thing that's so silly about it, as in the case of Hassan Almrei. He was on the GPS. He didn't have a family to go out with, so he was stuck at home. He was allowed to go pray if he took a taxi, but otherwise, for the most part, he was really under house arrest with the GPS.
In his case, he won. He was found not to be a security threat, and the next day he was completely free. Go figure. Why is he all of a sudden one day not a threat and the day before he has to have a GPS and house arrest? The conditions were too strict.